Dithiopyr is a well known pre-emergent herbicide used to prevent crabgrass and annual bluegrass (poa annua) along with several other broadleaf weeds. This formulation also contains 7% potash which aids the turf in stress recovery so not only are you preventing problem weeds and grasses, you are feeding the turf what it needs.
Contains Dithiopyr (.172%) and Potassium (7%).
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